Lipid X 

Lipid X is a 2,3-diacylglucosamine-1-phosphate that serves as the monosaccharide precursor of lipid A, possessing both LPS antagonist and weak agonist activities. Lipid X exerts protective effects by inhibiting tumor necrosis factor production, monocyte procoagulant activity, and neutrophil priming. Lipid X may induce transient pulmonary hypertension, neutropenia, and mild pyrogenic effects in laboratory animals. Lipid X has low toxicity and no in vitro antibacterial activity, but it significantly reduces mortality following Gram-negative bacterial infection and endotoxin exposure. Lipid X tends to accumulate in liver tissue, binds to circulating cellular components, and can be converted to lipid Y through transesterification. Lipid X can be used in research on Gram-negative bacterial sepsis, endotoxemia, and associated pulmonary hypertension^[1][2][3][4].

Lipid X (0-1.0 mM; 0-60 min) is converted to lipid Y by E. coli membrane-bound palmitoyltransferase, with formation linear with incubation time for up to 60 min and linear with membrane protein concentration up to 1.5 mg/mL, and exhibiting a concentration-dependent increase in product formation that approaches saturation at 1 mM lipid X^[1].
Lipid X (10 μg/mL) exhibits no in vitro antimicrobial activity against E. coli (ATCC 25922) and does not enhance ticarcillin-mediated bacterial killing^[2].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

Lipid X (1000 μg; intravenous injection; single administration; two administrations) alone produces a short-term, mild improvement in the survival rate of neutropenic mice with E. coli sepsis; when combined with Ticarcillin (HY-139805), it increases the survival rate by 2 to 4 times and reduces the effective dose of Ticarcillin required for 50% mouse survival by up to 4.5 times^[2].
A single dose of Lipid X (750 μg) reduces the mortality rate of LPS-induced endotoxemia in C57BL/10 mice^[3].
Lipid X protects sheep from LPS-induced death, alleviates LPS-induced pulmonary hypertension in both early and late stages, and protects neutropenic mice from fatal Gram-negative bacterial infection^[3].
Pretreatment with Lipid X (100-200 μg/kg; intravenous injection; bolus; single administration 1 hour prior to endotoxin challenge) results in 100% survival of sheep subjected to lethal E. coli endotoxin challenge, and significantly alleviates endotoxin-induced pulmonary arterial hypertension and fever^[4].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

711.86

C₃₄H₆₆NO₁₂P

86559-73-1

O[C@H]1[C@H](OC(C[C@H](O)CCCCCCCCCCC)=O)[C@@H](NC(C[C@H](O)CCCCCCCCCCC)=O)[C@@H](OP(O)(O)=O)O[C@@H]1CO

Room temperature in continental US; may vary elsewhere.

Please store the product under the recommended conditions in the Certificate of Analysis.

• [1]. Brozek K A, et al. Biosynthesis of lipid A precursors in Escherichia coli. A membrane-bound enzyme that transfers a palmitoyl residue from a glycerophospholipid to lipid X[J]. Journal of Biological Chemistry, 1987, 262(11): 5170-5179.

  [2]. Golenbock DT, et al. Lipid X protects mice against fatal Escherichia coli infection. Infect Immun. 1988;56(4):779-784.  [Content Brief]

  [3]. Golenbock DT, et al. Elimination and tissue distribution of the monosaccharide lipid A precursor, lipid X, in mice and sheep. Antimicrob Agents Chemother. 1988;32(1):37-41.  [Content Brief]

  [4]. Golenbock DT, et al. Lipid X ameliorates pulmonary hypertension and protects sheep from death due to endotoxin. Infect Immun. 1987;55(10):2471-2476.  [Content Brief]